John should chime in as he is the resident expert on 383's. I think the hardest part is finding good piston w/o spending a ton of cash. BUT if you are going to boost it compression shouldn't be an issue. Fast is relevant to the size of your wallet. And depends on what you already have. If you have nothing you'd probably better of starting w/ a 400 or 440. As the cost of internals is all the same. A lot depends on what you want the car for. If you are looking at making 450, there's no need to boost it. If you want to make 550+ of usable power, (meaning drive it anywhere) than yes boost is much better.